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31.
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以水性饱和聚酯树脂为基体树脂,以甲醚化氨基树脂为交联剂,以水性闪光铝银粉为效应颜料,以改性乙烯-醋酸乙烯共聚物蜡乳液为定向排列剂,在基材润湿剂、消泡剂、流平剂、中和剂、增稠剂、助溶剂、去离子水等的配合下制得水性金属闪光底色漆。涂膜于160℃×20 min条件下固化,具有VOC(挥发性有机化合物)含量低、硬度高、抗冲击、附着力强、闪光效果好、防腐性能优异、绿色环保、施工安全方便等优点。 相似文献
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Sason Shaik Miri Karni David Danovich Yitzhak Apeloig 《Israel journal of chemistry》2015,55(11-12):1167-1176
We tell the story of the Lise Meitner-Minerva Center, its establishment and activities, its members and their scientific activity, and its instrumental role in weaving intense relationships with the theoretical community in Germany, and in amalgamating the Israeli community of computational quantum chemistry into a national center that enjoys a high international reputation. 相似文献
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The Office of Technology Assessment (OTA), which was created by the Technology Assignment Act of 1972, was—and still remains even after its abolishment in 1995—a unique congressional agency. OTA provided members of Congress with their own means of understanding and evaluating complex science and technology matters—of which there are no shortages. It spurred an entire literature of academic research both about OTA and the idea of technology assessment more generally. Understanding the legislative history and implementation of the Technology Assessment Act is crucial not just for scholarship, though. OTA was a blueprint for institutionalizing politically accountable technology assessment. Even as technologies advance at rapid rates, OTA still offers valuable lessons that scholars and policy-makers alike ought to glean. This paper places OTA in a contemporary context of (institutionalized) technology assessment. It contributes to a better understanding of OTA's origins by tracing its lineage to a set of federal reports beginning in 1929. It then analyzes OTA's response to pragmatic implementation questions of how to strike a balance between speed, depth, scope, and temporal focus. Lastly, it uses a public values framework to critique OTA's failure to adequately incorporate participatory elements into its processes. 相似文献
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汽车路况网的概念源于数字城市的概念,通过研究网络、实时数据库和汽车智能,实现安全的交通网络。研究的语言一般应用Lisp语言,数据库为实时数据库。 相似文献
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Monopiles and gravity base foundations (GBF) are two of the most commonly used foundations for offshore wind turbines. As resonance can cause damage and even failure of wind turbines, understanding the difference between the dynamic responses of monopiles and GBFs under free vibration is important. However there is little experimental data regarding their natural frequency, especially from model tests carried out at correct stress levels. This paper presents the results of novel monopile and GBF tests using a centrifuge to directly determine the natural frequency (fn) of the foundation-soil system. The natural frequencies of wind turbine monopiles and GBFs in centrifuge models were measured during harmonic loading using a piezo-actuator, with the results confirming that soil-structure interaction must be considered to obtain the system’s natural frequency as this frequency reduces substantially from fixed-base values. These results will contribute in preventing resonance induced damage in wind-turbines. 相似文献